Seating unit



Nov. 8, 1966 H. D. CHAPMAN ET AL 3,284,132

' SEATING UNIT Filed July 1, 1965 2 Sheets-Sheet 1 57 mm,w1, ,m4/M OM g5 NOV. 8, 1966 PM N ET AL 3,284,132

SEATING UNIT Filed July 1. 1965 2 Sheets-Sheet 2 [22 v E .z: zur'sHOWAQD 0. CHAPMAN HEIVEYGEAIVKE ly MM, M 1 9 %5 United States Patent3,284,132 SEATING UNIT Howard D. Chapman, Highland Park, and Henry C.Banke, Chicago, 11111., assignors to Clarin Mfg. Co., Chicago, Ill., acorporation of Illinois Filed July 1, 1965, Ser. No. 468,307 Claims.(Cl. 297-162) The present invention relates to seating units and, moreparticularly, to seating units which include a detachable arm assembly.

Seating units provided for use in institutions such as schools,hospitals, industrial plants :and the like should be capable offunctioning equally well in each of a number of differing situations.For example, such seating units frequently are used to accommodateguests at lectures and the like and thus preferably include a tablet armto support books and writing materials. On the other hand, these sameseating units are often called upon for use in auditorium or informalsocial seating where a conventional arm rest rather than a tablet arm ismore appropriate. Still other situations may arise, however, in whichthe seating units are used in conjunction with tables and the like, asin dining halls or conference rooms and, hence, an arm rest of any formmay not only be unnecessary but undesirable.

Thus, there is a need for seating units which include readily attachableand detachable arm assemblies, either in the form of a tablet arm or aconventional arm rest, which will thereby render the seating unitsuseful in a variety of circumstances.

In order that such seating units with detachable arm assemblies may bestserve their intended functions, the arm assemblies are desirablyattached to the remainder of the Unit in such a manner that they willnot weaken the unit, place undue strain upon certain components thereof,or upset the overall balance of the unit. Also, the arm assemblies mustbe an inexpensive accessory to the unit, must be rigid and sturdy, andmust be capable of being securely attached without any tendency toloosen or Wobble.

Accordingly, it is the principal object of the present invention toprovide an improved seating unit which includes a detachable armassembly.

Another object of the invention is to provide an improved arm assemblyparticularly adapted to be detachably mounted on a chair.

A further object of the invention is to provide an improved seating unitwhich includes a detachable arm assembly and which possesses to agreater or lesser degree all of the desirable characteristics enumeratedabove.

Other objects and advantages of the invention will become apparent withreference to the following description and the accompanying drawings.

In the drawings:

FIGURE 1 is a perspective view of a seating unit showing various of thefeatures of the invention;

FIGURE 2 is an enlarged side elevational view of the seating unit ofFIGURE 1;

FIGURE 3 is a fragmentary partially exploded bottom view of the seatingunit of FIGURE 2;

FIGURE 4 is a side-elevational view of the arm assembly of the seatingunit of FIGURE 2 as viewed from the opposite direction of that figure;and

FIGURE 5 is a sectional plan view taken along line 5--5 of FIGURE 2.

Very generally, there is illustrated in the drawings a seating unitshowing various of the features of the present invention. Asillustrated, the seating unit comprises a chair 12 on which isdetachably mounted an arm assembly 14. The chair 12 includes abody-supporting shell 16 which is preferably molded, as from a fiberreinforced resin, to define a seat 13 and a backrest 20, each of whichmay be padded as at 22 if desired. The shell 16 is attached to andsupported on a base structure 24 comprising two pairs of leg members 26,one of which depends from each side of the seat. 18. The leg members 26of each pair are downwardly divergent relative to each other and aredefined by outwardly extending end portions of a pair of generallyU-shaped tubular members 28 (FIG. 3) which members also defineintermediate bight portions 30, referred to in greater detail shortly.The leg members are tapered toward their outer ends to provide .a moregraceful and pleasing appearance for the chair, and each of the outerends has detachably affixed thereto a foot in the form of a universallymounted pad or button 32 constructed to permit swivelli-ng movement ofthe pad relative to the leg member to thereby ensure full supportingengagement between the pad and the supporting surface.

The bight portions of the U-shaped tubular members 28 extendtransversely across the undersurface of the seat 18 from side to sideand are bent in an arcuate shape. Each of a pair of horizontally spacedelongated metallic strips 33 is secured, as by welding or the like, tothe upper surfaces of the .bight portions 30 in spanning relationthereto and each includes an upwardly offset flange portion 34 at itsforward end adapted to receive a bolt 36 to facilitate attachment of thebase 24 to the undersurface of the seat 18. A second hole (not shown) isalso provided in each of the strips 34 in rearwardly spaced relation tothe forward ends thereof to receive a fastener 38 which also serves toattach the base 24 to the seat.

Attached to the outer surfaces of each pair of diverging leg members 26is a bracket 40 adapted for releasable interconnection with a matingbracket of an adjacent chair to facilitate linking of the chairs in sideby side relation. In addition, the particular form of brackets shown inthe illustrated embodiment serve to interconnect and brace the legmembers adjacent each side of the chair. These brackets and theirfunction are disclosed in detail in United States Patent No. 3,084,977and such disclosure is incorporated herein by reference.

To provide for vertical stacking of two or more of the chairs 12, aswell as to facilitate mounting of the arm assembly 14 on a single chair,a stud 42 is provided on each leg member 26 and projects outwardly fromthe outer surface thereof immediately above each of the brackets 40.When two chairs are stack-ed one upon the other the studs 42 are engagedby the lower edge of a corresponding bracket of a stacked overlyingchair. A recess 43 is formed in the lower edge of each of the bracketsto receive the studs of an underlying chair. When an arm assembly ismounted on the chair, it rests upon and is partially supported by theupper edge of the studs, as hereinafter described.

The arm assembly 14 of the illustrated. embodiment comprises generally aframe 44 provided at its upper end with a pair of hinged brackets 46which pivotally secure a tablet arm 48 to the frame. A clamp 50 isprovided at the lower end of the frame 44 and serves to detachablysecure the frame to the leg members 26 at one side of the chair.

More specifically, the frame 44 comprises a post 52 of hollow tubularconstruction and of square cross sectional configuration which occupiesa generally vertical position when the arm assembly is secured to thechair. A brace 54 of similar tubular construction projects forwardly andupwardly from adjacent the lower end of the post 52 and is soproportioned as to place its upper end slightly above the upper end ofthe post 52,. thereby providing the tablet arm with a slight upwardinclination from back to front. The upper ends of each the post andbrace are closed by a cap 55 of a suitable material such as plasticwhich defines a generally horizontal upper surface for each member.

The hinge brackets 46 are generally identical and each comprises asomewhat triangular shaped plate 56 which is welded to the outer sidesurface of the frame post and brace respectively adjacent the upper endsthereof and with their upper edges inclined at the slight angle to thehorizontal assumed by the tablet arm. The ends of the plates 56 areoffset to form ears 58 which project away from the chair when the armassembly is mounted thereon, and each ear is provided with an opening toreceive a rivet 60 which pivotally secures a channel 62 to the plate.The rivets of both brackets define a single axis which is disposed at anangle to the horizontal similar to that of the tablet arm 48.

Each channel 62 includes a web 64 bolted to the under surface of thetablet arm 48 and is provided with an up standing flange 66 at each ofopposite ends. Each flange includes an opening which receives one of therivets 60 to pivotally interconnect the plate and channel. The axisdefined by the rivets 60, the plane of the webs 64, and the tablet arm48, are all disposed at a slight angle to the horizontal.

The tablet arm, as supported by the brackets 46, is pivotable between anupright position (not shown) in which it lies in a generally verticalplane, and an operative position, as seen in FIGURES 1-4. When thetablet arm is in the operative position (FIG. 4), the webs 66 of thechannels 62 overlie and are engaged by the upper ends of the post 52 andbrace 54. In order to provide the tablet arm with a particularlydesirable disposition relative to the chair, that portion of the web 66which is engaged by the post and brace is offset to provide aprotuberance 68 having a generally normal leading edge 70 and a surface72 which is disposed at a slight angle to the web and which is generallyhorizontal when the tablet arm is in the operative position despite theoverall inclination of the web 66. This protuberance causes that edge ofthe tablet arm which overhangs the seat 18 to be at a slightly higherelevation than that edge which is adjacent the outer side edge of thechair, since the protuberance is located in spaced relation to the axisdefined by the rivets 60 and about which the tablet arm rotate. Thisinclination is felt to increase the comfortable use of the tablet arm bythe user. In addition, the surface 72 of the offset provides a generallyhorizontal shoulder which the generally horizontal upper surface of thecaps 55 of the post or brace may abut.

In the illustrated embodiment, the tablet arm 48 i defined by a largeboard of somewhat L-shaped configuration. It should be clear, however,that a conventional form of arm rest might also be secured to the upperend of the frame 44 to render the seating unit more pecifically adaptedto other circumstances. When a conventional form of arm rest isemployed, the use of rigid brackets (not shown) rather than the hingedbrackets 46 would be more desirable.

The clamp 50 is provided at the lower end of the post 52 and comprisesan elongated clamping strip 74 welded to the lower end of the outersurface of the post in generally transverse relation thereto. The endedges of the strip are canted downwardly and outwardly and the portionsof the strip adjacent the ends are curved so as to enable the strip topartially encircle and intimately engage the outer surface of thegenerally cylindrical downwardly divergent upper portions of the legs 26of the chair. The strip 74 thus defines the outer portion of each of apair of downwardly diverging channels within which the legs 26 arereceived.

Secured to the inner face of the clamping strip 74 generally centrallythereof, and secured as well to the lower end of the post 52, is aC-shaped angle member 76 formed to provide upper and lower flanges 78and 80 respectively interconnected by a web 82. The upper flange 78 isof lesser width than the lower flange 80 and the web 82 includesdownwardly diverging side edges so as to render it of somewhattrapezoidal configuration similar to the configuration of the spaceintermediate the upper portion of the leg members 26. The angle memberis arranged with the web 82 welded to the inner face of the strip 74 andwith the upper flange 78 welded to the lower end of the post 52. Theangle member 76 is of lesser width than the strip 74 so as not tointerfere with the disposition of the legs 26 within the channels ateach end of the strip. In effect, the edges of the flanges of the anglemember 76 define the inner edges of the channels. Bolts 84 extendthrough the strip 74 and through the web 82 of the angle member and arewelded in place.

The remainder of the clamp 50 is defined by a second clamping strip 86which, generally speaking, is a mirror image of the previously referredto strip 74. More specifically, the strip 86 has downwardly divergingside edges and the portions of the strip adjacent the end edges arecurved so as to enable the strip to partially encircle and intimatelyengage the inner surface of the downwardly divergent upper portions ofthe legs 26. The strip 86 thus cooperates with the strip 74 and theangle member 76 to define the pair of channels, previously referred to,which diverge downwardly and outwardly and receive the legs 26. Holesare provided in the strip 86 to receive the bolts 84, and nuts 88 areprovided on the bolts to urge the strip 86 in the direction of the strip74 to clamp the legs within the channels.

The arm assembly is attached to the chair by positioning of the armassembly adjacent the side of the chair (the right side in theembodiment illustrated) with the outer surface of the upper ends of theleg members disposed in engagement with the inner surfaces of the curvedportions of the strip 74 and with the angle member '76 and the bolts 84projecting inwardly between the legs. In addition, the lower edge of thestrip 74 rests upon the studs 42 which project from the sides of the legmembers 26. The clamping strip 86' is then put in place and the nuts 88are placed on the bolts 84 so as to draw the clamping strip into tight,intimate engagement with the inner side surface of the leg members. Thelegs are thus engaged on both their inner and outer surfaces, therebyinsuring an intimate and tight connection ridigified by the angle member76.

An improved seating unit, and arm assembly for a seating unit, has thusbeen provided which renders the seating unit adaptable to any one ofseveral diverse situations and thus particularly useful for institutionsand the like. More specifically, the readily attachable or detachablearm assembly, when provided with a tablet arm as shown in theillustrated embodiment, renders the chair particularly suitable forlectures and the like. When the arm assembly is provided with aconventional arm rest, the chair is rendered particularly useful forauditorium or other informal use. However, the arm assembly can becompletely removed from the chair without leaving unsightly brackets orfixtures attached to the chair, thus rendering the chair useful in anyof a number of other situations where an arm rest is not only notnecessary but, perhaps, undesirable.

While the seating unit and arm assembly of the present invention havebeen shown and described with respect to one specific embodimentthereof, it should be apparent that various structural modifications maybe made in the disclosed seating unit and arm assembly without departingfrom the scope of the invention.

Various of the features of the invention are set forth in the followingclaims.

What is claimed is:

1. An arm assembly for use with a chair having a pair of downwardlydiverging legs at each side, which arm assembly prises a frame, an armrest mounted on the upper end of said frame, and means at the lower endof said frEU K; adapted. to. detachably clamp said frame to each of thelegs at one side of the chair, said means including a first clampingstrip fixedly secured to the lower end of said frame and a secondclamping strip, one of said clamping strips including end portionsformed to partially encircle and intimately engage the upper portion ofthe outer surface of each leg member at one side of the chair and theother of said clamping strips including end portions formed to partiallyencircle and intimately engage the upper portion of the inner surface ofeach leg member opposite those portions of the outer surfaces of the legmembers adapted to be engaged by said one clamping strip, the endportions of said second clamping strip being adapted to cooperate withthe end portions of said first clamping strip to define a pair ofchannels diverging downwardly at an angle equal to the angle ofdivergence of the leg members, and means for urging said first andsecond clamping strips toward each other so as to maintain said stripsin clamping engagement with each of the leg members at one side of thechair.

2. An "arm assembly for use with a chair having a pair of downwardlydiverging legs at each side, which arm assembly comprises a frame,including an upright post, an arm rest mounted on the upper end of saidframe, and means at the lower end of said frame adapted to detachablyclamp said frame to each of the legs at one side of the chair, saidmeans including a first clamping strip fixedly secured to the lower endof said post, said strip including end portions formed to partiallyencircle and intimately engage the upper portion of the outer surface ofeach leg member at one side of the chair, an angle member secured to theinner surface of said first clamping strip and including an upper flangesecured to the lower end of said post, said angle member also includinga lower flange spaced downwardly from said upper flange having a widthgreater than said upper flange, a second clamping strip including endportions formed to partially encircle and intimately engage the upperportion of the inner surface of each leg member opposite those portionsof the outer surfaces of the leg members adapted to be engaged by saidfirst clamping strip, the end portions of said second clamping stripbeing adapted :to cooperate with the end portions of said first clampingstrip and with said angle member to define a pair of channels diveringdownwardly at an angle equal to the angle of divergence of the legmembers, and means for urging said first and second clamping stripstoward each other so as to maintain said strips in clamping engagementwith each of the leg members at one side of the chair.

3. A seating unit comprising a seat and back rest, a base defined by apair of legs diverging downwardly at each side of said seat, and an armassembly detachably mounted on one of said pair of legs comprising aframe, an arm (rest mounted :on the upper end of said frame, and meansat the lower end of said frame detachably clamp-ing said frame to eachof the legs at one side of the chair, said means including a firstclamping strip fixedly secured to the lower end of said frame and asecond clamping strip, one of said clamping strips including endportions formed to partially encircle and intimately engage the upperportion of the outer surface of each leg member at one side of the chairand the other of said strips including end portions formed to partiallyencircle and intimately engage the upper portion of the inner surface ofeach leg mem ber opposite those portions of the outer surfaces of theleg members adapted to be engaged by said one clamping strip, the endportions of said second clamping strip being adapted to cooperate withthe end portions of said first clamping strip to define a pair ofchannels diverging downwardly at an angle equal to the angel ofdivergence of the leg members, and means for urging said first andsecond clamping strips toward each other so as to maintain said stripsin clamping engagement with each of the leg members at one side of thechair.

4. A seating unit in accordance with claim 3 wherein each of said one ofsaid pair of legs is provided with a projecting lug positioned so as tobe engaged by said detachable clamping means to provide vertical supportfor said arm assembly.

5. An arm assembly in accordance with claim 1 wherein said arm rest isin the form of a tablet arm mounted on said frame [for pivotal movementbetween an operative and an out-of-the-way position.

References Cited by the Examiner UNITED STATES PATENTS 939,764 11/1909Vickers et al. 297--16 l X 3,048,441 8/ 1 9 62 Rose 297422 X 3,084,9774/ 1963 Chapman 297-239 3,174,795 3/1965 Chapman et al. 297160 FRANCISK. ZUGEL, Acting Primary Examiner.

CASMIR A. NUNBERG, Examiner.

1. AN ARM ASSEMBLY FOR USE WITH A CHAIR HAVING A PAIR OF DOWNWARDLYDIVERGING LEGS AT EACH SIDE, WHICH ARM ASSEMBLY COMPRISES A FRAME, ANARM REST MOUNTED ON THE UPPER END OF SAID FRAME, AND MEANS AT THE LOWEREND OF SAID FRAME ADAPTED TO DETACHABLY CLAMP SAID FRAME TO EACH OF THELEGS AT ONE SIDE OF THE CHAIR, SAID MEANS INCLUDING A FIRST CLAMPINGSTRIP FIXEDLY SECURED TO THE LOWER END OF SAID FRAME AND A SECONDCLAMPING STRIP, ONE OF SAID CLAMPING STRIPS INCLUDING END PORTIONSFORMED TO PARTIALLY ENCIRCLE AND INTIMATELY ENGAGE THE UPPER PORTION OFTHE OUTER SURFACE OF EACH LEG MEMBER AT ONE SIDE OF THE CHAIR AND THEOTHER OF SAID CLAMPING STRIPS INCLUDING END PORTIONS FORMED TO PARTIALLYENCIRCLE AND INTIMATELY ENGAGE THE UPPER PORTION OF THE INNER SURFACE OFEACH LEG MEMBER OPPOSITE THOSE PORTIONS OF THE OUTER SURFACES OF THE LEGMEMBERS ADAPTED TO BE ENGAGED BY SAID ONE CLAMPING STRIP, THE ENDPORTIONS OF SAID SECOND CLAMPING STRIP BEING ADAPTED TO COOPERATE WITHTHE END PORTIONS OF SAID FIRST CLAMPING STRIP TO DEFINE A PAIR OFCHANNELS DIVERGING DOWNWARDLY AT AN ANGLE EQUAL TO THE ANGLE OFDIVERGENCE OF THE LEG MEMBERS, AND MEANS FOR URGING SAID FIRST ANDSECOND CLAMPING STRIPS TOWARD EACH OTHER SO AS TO MAINTAIN SAID STRIPSIN CLAMPING ENGAGEMENT WITH EACH OF THE LEG MEMBERS AT ONE SIDE OF THECHAIR.